A file managing method of an information recording/reproducing apparatus
for managing a recording information file by recording a directory to
manage the recording information file into a directory region provided on
an information recording medium. In the file managing method, erasure
information regarding the recording information file to be erased is
recorded into the directory region in order to logically erase the
recording information file. The recording information file which has
logically been erased is reproduced by using the erasure information so as
again to reproduce the recording information file which has logically been
erased.

This application is a continuation of application Ser. No. 08/285,754,
filed Aug. 3, 1994, which was a continuation of application Ser. No.
07/758,199 filed Sep. 12, 1991 now abandoned.

Claims

What is claimed is:

1. A file managing method for use in an information recording/reproducing
apparatus for managing recording information files by recording
directories to manage the recording information files into directory
regions provided on an information recording medium, said method
comprising the steps of:

forming onto the directory regions an erasure directory regarding the
recording information files to be erased in order to logically erase the
recording information files;

reading out directories,including the erasure directory, from the directory
regions;

discriminating whether or not each of the read directories is an erasure
directory;

managing, in an erasure mode, the recording information files corresponding
to the directories each discriminated as being an erasure directory in
said discriminating step, in a particular order, and managing, in a normal
mode, the recording information files corresponding to the directories
each discriminated as not being an erasure directory in said
discriminating step; and

displaying, in a displaying device, file names of the recording information
files in said particular order, managed by the erasure mode, by selecting
the erasure mode when a logically erased recording information file is
reproduced, and reproducing a desired logically erased recording
information file by a user selecting the file name of the desired
recording information file, wherein said particular order is order of
erasure, or, for any plurality of files corresponding to erasure
directories having the same file name, is the order of erasure from among
that plurality of files.

2. A file managing method for use in an information recording/reproducing
apparatus for managing recording data files by recording directories to
manage the recording data files into directory regions provided on an
information recording medium, said method comprising the steps of:

forming onto the directory regions an erasure directory, including a serial
number, regarding the recording data files to be erased in order to
logically erase the recording data files;

reading out directories, including the erasure directory, from the
directory regions;

discriminating whether or not each of the read directories is an erausre
directory;

managing, in an erasure mode, the recording data files corresponding to the
directories each discriminated as being an erasure directory in said
discriminating step, in a particular order by using said serial number,
and managing, in a normal mode, the recording data files corresponding to
the directories each discriminated as not being an erasure directory in
said discriminating step; and

displaying, in a displaying device, file names of the recording data files
in said particular order, managed by the erasure mode by selecting the
erasure mode when a logically erased recording information file is
reproduced, and reproducing a desired logically erased recording data file
by a user selecting the file name of the desired recording data file,
wherein said particular order is order of erasure, or, for any plurality
of files corresponding to erasure directories having the same file name,
is the order of erasure from among that plurality of files.

3. A method according to claim 2, wherein the serial numbers are managed
for every file of a same file name.

4. A method according to claim 2, wherein the serial numbers indicate the
number of erasing operation times of the files.

5. A method according to claim 1, wherein the erasure information is
recorded into predetermined regions of directories of the files which are
logically erased by existence of the erasure information.

6. A method according to claim 2, wherein the erasure information is
recorded into predetermined regions of directories of the files which are
logically erased by existence of the erasure information.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a file managing method of an information
recording/reproducing apparatus for recording or/and reproducing
information onto/from an information recording medium.

2. Related Background Art

A directory is used as a file managing method for handling a large quantity
of file data in a floppy disc, a magnetic hard disc, a magneto-optical
disc, an IC card, or the like.

The directory is used as an index of a file. A file name, a time and date
of the formation of the file, a writing position (head track number) of
the corresponding file, and the like are included in the directory. When a
new file is formed, a new directory is formed. If there is an unnecessary
file, the corresponding directory is deleted, so that the files can be
easily managed.

In the above system using an erasable and rewritable information recording
medium such as a magnetic/magento-optical recording medium or IC card,
information can be easily erased and rewritten.

In the above case, even if the file has logically been erased, the erased
file physically exists so long as the region where such a file existed is
not re-used.

However, when a part of or all of the above region has been used by the
recording of another file, the file which has logically been erased is
also physically erased.

Fundamentally, in the system using the above information recording medium,
the concept such each of the erased files is preserved and managed, is not
found.

On the other hand, a WORM type information recording medium whose use has
been started in recent years, for instance, an optical card, is small and
light and is convenient to carry. Such an optical card has a relatively
large capacity and is cheap. From the above viewpoints, a large demand of
such an optical card is expected as a recording medium to manage personal
information.

A file managing method in such a system using the optical card as an
information recording medium largely differs from a file managing method
in the system using a magnetic recording medium or the like as mentioned
above.

A structure of the optical card and the information recording/reproducing
principle will be first explained.

FIG. 1A is a schematic plan view showing an example of an optical card.
FIG. 1B is a cross sectional view taken along the line B--B in FIG. 1A.

In the diagrams, reference numeral 1 denotes an optical card. The surface
of the optical card mainly comprises an information recording region 51
and a blank region 52. A logo 50 can be inserted in the blank region 52 so
that the user can visually discriminate the kind, application, and the
like of the optical card. A plurality of tracks 54 for tracking which have
been preformated for auto tracking are arranged in parallel in the
information recording region 51. Portions among adjacent tracking tracks
are set to information tracks 55 on which information is recorded.

As shown in FIG. 1B, the optical card 1 comprises a plurality of layers.
Reference numeral 56 denotes a transparent protecting layer and 57
indicates a recording layer. The recording layer is formed by, for
instance, the silver salt system, dye system, chalcogen system, or the
like. A boundary between the transparent protecting layer 56 and the
recording layer 57 has a step shape, so that the tracking tracks 54 and
the information tracks 55 are formed. Reference numeral 59 denotes a
substrate. The substrate 59 and the recording layer 57 are jointed by an
adhesive agent layer 58.

Information is recorded onto such an optical card 1 by scanning the
information tracks 55 while a light beam converged into a microspot shape
is modulated in accordance with recording information. The information is
recorded as an information bit train which can be optically detected.

Since the information bit train is formed by a physical change such as
deformation, color change, or the like by light and heat, it is impossible
physically to erase the information bit train which has once been recorded
and again to use the erased information bit train region as a recording
region.

Information is reproduced from the recording medium by scanning the
information bit train on the information tracks by a light beam spot of a
predetermined power such that no recording is executed onto the medium and
by detecting the reflected light or transmitted light from the medium.

A file management in the system using an optical card as an information
recording medium will now be described.

When a certain amount of information is recorded onto the optical card, two
kinds of information for a data file the filed information itself and a
directory to manage the data file, are recorded.

At this time, in the information recording region 51 in FIG. 1A, by
recording the directory and the data file into different recording
regions, file management can be made easy.

Further other information is sequentially recorded into the next
non-recorded regions of the data file or directory which has already
existed.

The erasure of the file will now be described. To erase the unnecessary
file, information which is obtained by adding information indicative of
the completion of the erasure to the information of the directory to
manage the file is newly recorded and the file corresponding to the new
information is not read out on the system, thereby logically erasing the
file.

In the system using the optical card as an information recording medium,
the file management as mentioned above is performed.

In recent years, personal information has been being managed by various
recording media. There are a variety of application fields. For instance,
further development such as applications to a medical information
management, a security information management, a parts management, an ID
card, a prepaid card, and the like is expected in future.

However, in such a management system of personal information, erroneous
erasure and destruction of the recorded information, and operation and
forgery of information by others becomes the maximum problem. There are
many cases where such a problem causes a problem of human rights.

For such a problem, in the magnetic/magneto-optical recording medium or IC
card, since the file is physically erased, such a medium is improper as a
recording medium to manage personal information and it is impossible to
cope with the occurrence of the problem.

Although the optical card is considered to be the optimum medium as a
recording medium to manage personal information with respect to a point
that the recorded information is not physically erased, the conventional
system using the optical card uses a file managing method similar to that
of the system using the magnetic/magneto-optical recording medium or IC
card. Therefore, the information which has once logically been erased
cannot be reproduced again.

The above point denotes that the valuable feature of the optical card such
that the recorded information is not physically erased although it has
logically been erased is not adequately utilized.

SUMMARY OF THE INVENTION

The invention is made in consideration of the above problems and it is an
object of the invention to provide a file managing method which can read
out a file which has logically been erased.

The above object is accomplished by a file managing method for an
information recording/reproducing apparatus for managing a recording
information file by recording a directory to manage the recording
information file into a direction region provided on an information
recording medium, comprising the steps of: recording erasure information
regarding the recording information file to be erased into the directory
region in order to logically erase the recording information file; and
reproducing the recording information file which has logically been
erasure by using the erasion information to again reproduce the recording
information file which has logically been erased.

The above object is also accomplished by a file managing method for an
information recording/reproducing apparatus for managing a recording data
file by recording a directory to manage the recording data file into a
directory region provided on an information recording medium, comprising
the steps of: recording erasure information regarding the recording data
file to be erased and information indicative of the serial number of the
erasure information into the directory region in order to logically erase
the recording data file; and reproducing the logically erased recording
data file by using the erasure information and the serial number of the
erasure information in order to again reproduce the logically erased
recording data file.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a plan view showing an example of an optical card;

FIG. 1B a cross sectional view of FIG. 1A;

FIG. 2 is a diagram showing the first embodiment of a file managing method
of the invention;

FIG. 3 shows an example of an information recording/reproducing apparatus
for executing a file managing method of the invention;

FIG. 4 is a flowchart when information is recorded in the first embodiment
of the file managing method of the invention;

FIG. 5 is a flowchart when information is reproduced in the first
embodiment of the file managing method of the invention;

FIG. 6 is a diagram showing the second embodiment of a file managing method
of the invention;

FIG. 7 is a flowchart when information is recorded in the second embodiment
of the file managing method of the invention;

FIG. 8 is a flowchart when information is reproduced in the second
embodiment of the file managing method of the invention;

FIG. 9 is a diagram showing a file managing method of a modification of the
second embodiment;

FIG. 10 is a diagram showing the third embodiment of a file managing method
of the invention;

FIG. 11 is a flowchart when information is recorded in the third embodiment
of the file managing method of the invention;

FIG. 12 is a flowchart when information is reproduced in the third
embodiment of the file managing method of the invention; and

FIG. 13 is a diagram showing a file managing method of a modification of
the third embodiment.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

An embodiment of the invention will be described in detail hereinbelow with
reference to the drawings. As an example of a directory format, the case
where it is used in an optical card will be explained.

First, an example of a structure of an information recording/reproducing
apparatus which is used to form a directory according to the invention
will be explained.

FIG. 3 is a schematic diagram of an example of a structure of the
information recording/reproducing apparatus which is used in the
invention.

An information recording/reproducing apparatus (hereinafter, referred to as
a drive) 31 is connected to an upper control apparatus (hereinafter,
referred to as a host) 32. Communication, control, etc. of data are
executed between the drive 31 and the host 32. An MPU 33 in the drive 31
has therein a ROM and a RAM. The MPU 33 mainly controls a card feed motor
37 and a head feed motor 36. An AT/AF control circuit 34 receives a signal
of a photodetector 39 and drives an AF actuator 40 and an AT actuator 41.
A modulation-demodulation circuit 35 executes the recording by changing a
light emission intensity of a light source 38 upon recording and
demodulates the data on the basis of the signal of the photo detector 39
upon reproduction. The host 32 executes transmission and reception of data
with the drive 31 and controls the recording and reproducing operations of
information in the directory section and the data section on the optical
card 1.

FIG. 2 is a diagram showing the first embodiment of a file managing method
of the invention.

Files 1 to 5, 3' and 5' in the data sections 21a to 25a, 23'a, and 25'a
file information of the files 3 and 5, and information necessary for the
file management have been written in directories 1 to 5, 3' and 5' and
erasure directories 3 and 5 in the directory sections 21 to 29.

Formats of the directory and the erasure directory are the same. The format
is constructed by a directory serial No. section 101, an erasure
information section 102, an erasure directory serial No. section 103, a
file name section 104, and other information section 105. One bit is
assigned to the erasure information section 102. At least one or more bits
are assigned to the erasure directory serial No. section 103.

One-byte information which is set to 1 in the case where the directory is
the erasure directory and is set to 0 when the directory is not the
erasure directory is recorded in the erasure information section 102. The
1-byte information is not always limited to 1 or 0 but any information
which can judge whether the directory is the erasure directory or not can
be used. The file which is managed by the erasure directory whose erasure
information is set to 1 belongs to a group of logically erased files which
are managed by erasure mode. The file which is managed by the directory
whose erasure information is set to 0 belongs to a group of logically
existing files which are managed by normal mode. Since the directories 3
and 5 are directories as objects to be erased, even if the erasure
information is set to 0, the directories 3 and 5 don't belong to a group
of files which are managed by normal mode.

FIG. 4 is a flowchart of the processing for the case of recording
information in the first embodiment of a file managing method of the
invention.

FIG. 5 is a flowchart of the processing for the case of reproducing
information in the first embodiment of a file managing method of the
invention.

The file managing method using the directory format will now be practically
explained hereinbelow with reference to FIGS. 2, 4, and 5.

In FIG. 2, the case where the content in the file 3 which is managed by the
directory 3 is corrected and is again recorded onto the optical card under
the same file name will now be considered.

It is now assumed that a mark (') is added to the newly recorded file name
in order to make the discrimination easy. The same shall also apply to the
directory names.

In FIGS. 2 and 4, information indicating that the file 3 is rewritten under
the same file name as a correction data file 3' of the file 3 is sent from
the host 32 to the MPU 33. In step 200, a check is made to see if the file
is erased or not. In an erasure directory format 201, the erasure
information section is set to 1 and the erasure directory serial No.
section is set to X=1. In step 203, a check is made to see if the file is
rewritten under the same file name or not. In step 204, the erasure
directory 3 is recorded into the directory section 25 on the optical card.
The file 3 is a file which has been erased on the optical card. The system
is constructed in a manner such that when two or more directories for the
same file name exist, the file of such a file name is regarded as an
erasure file.

The MPU 33 confirms that the erasure directory 3 has been recorded. A check
is again made in step 200 to see if the file is erased or not. In this
case, since the file 3' and the directory 3' are recorded, the corrected
content of the file 3 is first recorded as a file 3' into the data section
23a. The directory 3' to manage the file 3' is recorded into the directory
section 26 by setting both the erasure information section and the erasure
directory serial No. section to 0.

Thus, the file 3 which has been managed by the file group in the normal
mode is managed by the file group in the erasure mode since the erasure
directory 3 has been determined, The file 3' is newly managed by the file
group in the normal mode.

With respect to the file 5 and the directory 5 to manage the file 5 shown
in FIG. 1 as well, there are relations similar to those of the file 3
among the erasure directory 5, file 5' and directory 5'. The erasure
directory serial No., however, is set to X=2 in the erasure directory
format 103 and is recorded.

The case where the file is corrected and is again recorded under the same
file name has been described above. However, in the case of executing only
the erasure of the existing files, the answer in step 203 in the flowchart
is NO and only the erasure directory is written onto the optical card.

The serial No. of the erasure directory is the serial number indicative of
the recording order of the erasure directory on the optical card. It is
now assumed that the number of existing erasure directories can be decided
just after the optical card was inserted into the information
recording/reproducing apparatus.

A reproducing method of the information recorded on the optical card will
now be described with reference to FIGS. 2 and 5.

The information files 1 to 5, 3', and 5', their directories 1, 2, 4, 3',
and 5', and the erasure directories 3 and 5 which have been recorded on
the optical card are sent to the MPU 33 by the reproducing operation of
the information recording/reproducing apparatus by a command from the host
32. In step 300, the MPU 33 checks to see if the erasure information
section in each of the directory and the erasure directory has been set to
1 or not.

The files 3 and 5 corresponding to the erasure directories 3 and 5 whose
erasure information sections are set to 1 are stored into the erasure mode
region in the host 32. The files 1, 2, 4, 3', and 5' corresponding to the
directories 1, 2, 4, 3', and 5' whose erasure information sections are set
to 0 are stored into the (normal mode) region in the host 32. That is, in
step 300, a check is made to see if the reproduced information is
information which has been erased in the past or not, thereby distributing
the reproduced information.

For each file stored in the host 32 in one of the modes discussed above, by
selecting one or another mode, the file name can be displayed by a display
301 as shown in FIG. 5. It is now assumed that when the erasure mode is
selected, the file names and the erasure directory serial Nos. are
simultaneously displayed in order, beginning from the small serial No.
Thus, the career of the erased files can be discriminated. When the normal
mode is selected, the file names and the erasure directory serial Nos. are
displayed in accordance with the reading order from the optical card. By
selecting the file name, the content of each file can be also seen.

As described above, according to the invention, the logically existing
files and the logically erased files can be managed as separate file
groups. A file management is ordinarily progressed by the logically
existing file group. On the other hand, by selecting the erasure mode, the
group of files which have logically been erased in the past can be
retrieved in accordance with the serial Nos. of the erasure directories.

In the first embodiment, 0 has been recorded into the erasure information
section 102 and the erasure directory serial No. section 103 of each of
the directories 1, 2, 4, 3', and 5'. However, even if the sections 102 and
103 are held in a blank state without recording any data, an effect
similar to that in the first embodiment is also obviously obtained.

By management of the erasure directory serial Nos. in the first embodiment
for those files having the same file name, in the case where the same
files have been corrected many times and have been rewritten, by selecting
the file name, the erasure career and the contents of only the files
having such a file name can be retrieved. In the retrieval of the
logically erased files, thus, the function can be further improved.

Moreover, it is also possible to record the erasure directories from time
to time, once some predetermined number have been used, in a group into a
special region (not shown) on the optical card.

For the management of the erasure directories, it is also possible to
construct the apparatus in such a manner that only a predetermined number
of erasure directories are managed; for instance, assuming that such a
predetermined number is set to 5, when the erasing and updating operations
have been performed seven times, only five erasure directories are
displayed from the erasure directories having new erasure careers.

Even by the above construction, an effect similar to that of the first
embodiment can be obtained and the function of the file management can be
improved.

The second embodiment of a file managing method of the invention will now
be described.

In the second embodiment, the erasure directory serial Nos. is included in
the erasure information.

FIG. 6 is a diagram showing the second embodiment of a file managing method
of the invention.

The directory and the erasure directory have the same format. The format is
constructed by a directory serial No. section 601, an erasure information
section 602, a file name section 603, and other information section 604.
At least one or more bits are assigned to the erasure information section
602.

A serial No. consisting of a number of bytes indicating at which number the
erasure directory has been established in the optical card is recorded by
a numeral other than 0 into the erasure information section 602 if the
directory is the erasure directory. If the directory is not the erasure
directory, 0 is recorded into the erasure information section 602.

In the embodiment, if the erasure information has a numeral other than 0,
the directory is decided as an erasure directory. The file which is
managed by the erasure directory belongs to a group of logically erased
files which are managed in the erasure mode. The file which is managed by
the directory whose erasure information is set to 0 belongs to a group of
logically existing files which are managed in the normal mode. However,
since the directories in the directory sections 621, 624, 626, and 622 are
already the directories as objects to be erased, even if the erasure
information is equal to 0, they don't belong to the group of files which
are managed in the normal mode.

FIG. 7 is a flowchart of the processing for the case of recording
information in the second embodiment of a file managing method of the
invention.

FIG. 8 is a flowchart of the processing for the case of reproducing
information in the second embodiment of a file managing method of the
invention.

The second embodiment of the file managing method of the invention using
the directory format will now be practically explained hereinbelow with
reference to FIGS. 6, 7, and 8.

In FIG. 6, a case where the content of the file 1 which is managed by the
directory 1 of the directory serial No. 1 is corrected and is again
recorded onto the optical card by the same file name will now be
considered.

In FIGS. 6 and 7, information indicating that the file 1 is rewritten under
the same file name as a correction data file 1 of the file 1 is sent from
a host 732 to an MPU 733. In step 700, a check is made to see if the file
is erased or not. The erasure information section is set to 1 in an
erasure directory format 701. A check is made in step 703 to see if the
file is rewritten under the same file name or not. In step 704, the
erasure directory 1 is recorded into the directory section 623 on the
optical card. The contents of the file name section 603 and the other
information section 604 of the erasure directory 1 are the same as the
contents in the directory 1. The file 1 becomes a file which has first
been erased on the optical card.

The MPU 733 confirms that the erasure directory 1 has been recorded into
the directory section 623. In step 700, a check is again made to see if
the file is erased or not. In this case, since the correction data file 1
and the directory 1 of the directory serial No. 4 which manages the
correction data file 1 are recorded, the correction data file 1 is first
recorded as a file 1 into the file section. The directory 1 of the
directory serial No. 4 is subsequently recorded into the directory section
624 by setting the erasure information section to 0.

Thus, the file 1 which has been managed by the file group of the normal
mode is managed by the file group of the erasure mode since the erasure
directory 1 of the directory serial No. 3 has been determined. Thus, the
file 1 which is newly managed by the directory serial No. 4 is managed by
the file group of the normal mode.

In FIG. 6, the files are respectively erased by the directory Nos. 5, 7,
and 9. Further, with respect to the recording of the correction data files
and the management directories as well, they are managed by processes
similar to those in the foregoing file management. However, the erasure
information recorded in the erasure directories of the directory serial
Nos. 5, 7, and 9 is set to 2, 3, and 4 as shown in FIG. 6, respectively.

The erasure information of the erasure directories in the embodiment
indicate the serial Nos. showing the recording order of the erasure
directories of the optical card. The serial No. as erasure information
increases one by one each time the erasure directory is added. The number
of existing erasure directories is determined by detecting the erasure
information in the last erasure directory by reading out the directory
which is executed when the optical card is inserted into the information
recording/reproducing apparatus.

The case where the file is corrected and is again recorded by the same file
name has been described above. However, in the case of executing only the
erasure of the existing files, by deciding that the answer in step 703 in
the flowchart is NO, only the erasure directories are written onto the
optical card.

A reproducing method of the information recorded on the optical card will
now be described by using FIGS. 6 and 8.

The files in the data sections 621a, 622a, 621a1, 621a2, 622a1, and 621a3
which have been recorded on the optical card and the directories which
manages the files or the erasure directories are sent to the MPU 833 by
the reproducing operation of the information recording/reproducing
apparatus by a command from a host 832. In step 800, an MPU 833 checks to
see if each directory or each erasure information section in the erasure
directory is equal to 0 or not. A group of files which are managed by the
erasure directories of the directory serial Nos. 3, 5, 7, and 9 whose
erasure information sections are not 0 are stored into an (erasure mode)
region in the host 832.

A group of files which are managed by the directories of the directory
serial Nos. 8 and 10 whose erasure information sections are equal to 0 are
stored into a normal mode region in the host 832. That is, in step 800, a
check is made to see if the reproduced information is the information
which has been erased in the past or not, thereby distributing the
reproduced information.

For the file groups stored into the host 832 every mode, by selecting each
mode, the file names can be displayed on a display 801 as shown in FIG. 8.

At this time, when the erasion mode is selected, the file names and the
serial Nos. as erasion information thereof are simultaneously displayed in
order beginning from the small serial No. Thus, a career of the erased
files can be judged. When the normal mode is selected, they are displayed
in accordance with the reading order from the optical card.

By selecting the file names in both of the erasion mode and the normal
mode, the content of each file can be also seen.

As mentioned above, according to the invention, the logically existing
files and the logically erased files can be managed as separate file
groups. A file management is ordinarily progressed by a group of logically
existing files. On the other hand, by selecting the erasion mode, a group
of files which have logically been erased in the past can be retrieved in
accordance with the serial Nos. as erasion information of the erasure
directories.

In the second embodiment, a numeral of 0 has been recorded into the erasion
information section 602 of each directory. However, enen if the erassion
information sections 602 are held in a blank state without recording any
numeral, an effect similar to that in the second embodiment is obtained.

As shown in FIG. 9, by independently managing the serial Nos. as erasure
information of the erasure directories every file or the same file name,
an effect similar to that of the second embodiment can be also derived.
Further, in the retrieval of the logically erased files, the function can
be further improved.

Moreover, the erasure directories can be also recorded in a lump into a
special region (not shown) on the optical card on a unit basis of a
predetermined number when the number of erasure directories has reached
the predetermined number.

For the management of the erasure directories, it is also within the
invention to construct the apparatus in a manner such that only a
predetermined number of erasure directories are used as objects. For
instance, assuming that such a predetermined number is set to 5, when the
erasing and updating operations have been executed seven times, only five
erasure directories are displayed from the erasure directory having a new
erasure career.

By the above constructions, an effect similar to that of the second
embodiment can be also obtained. The function of the file management can
be improved.

The third embodiment of a file management method of the invention will now
be described.

In the third embodiment, a non-recorded region (region in which information
can be written later) is added to the directory and the erasure
information is recorded into the non-recorded region. Due to this, as
shown in the above first and second embodiments, it is not necessary to
record the erasure directories of the same file name into the directory
region. The space of the directory region can be saved.

The third embodiment will be described in detail hereinbelow with reference
to FIG. 10.

In the diagram, reference numerals 1021 to 1030 denote directory sections
and 1021a to 1030a indicate data sections. Among the directory sections
1021 to 1030, reference numerals 1021 to 1024, 1026, and 1027 indicate
erasure directories and other reference numerals 1025 and 1028 to 1030
indicate directories. On the other hand, the directory and the erasure
directory have the same format. The format is constructed by a directory
serial No. section 1101, a file name section 1102, other file management
information 1103, and a non-recorded region 1104 to record erasure
information. At least one or more bits are assigned to the non-recorded
region 1104.

A numeral 1 as erasure information indicative of the completion of the
erasure is recorded in the non-recorded region 1104 of each of the erasure
directories 1021 to 1024, 1026, and 1027 indicating that the files have
logically been erased. As such erasure information, any erasure
information which can be used as information such as a numeral, character,
symbol, or the like can be used. Nothing is recorded in the non-recorded
region of each of the directories 1025 and 1028 to 1030 and those regions
are held as space regions.

In the third embodiment, it is assumed that if 1 has been recorded in the
non-recorded region 1104, the directory is determined as an erasure
directory and that the file which is managed by the erasure directory
belongs to the group of logically erased files which are managed in the
erasure mode. The file which is managed by the directory in which no
information exists in the non-recorded region 1104 belongs to the group of
logically existing files which are managed in the normal mode.

FIG. 11 is a flowchart showing the processing for the case of recording
information by the file management method of the third embodiment. FIG. 12
is a flowchart showing the procesing for the case of reproducing
information by the file management method of the third embodiment. The
file management methods using the directory format mentioned above will
now be practically explained hereinbelow with reference to FIGS. 10, 11,
and 12.

It is now assumed that the erasure directory 1 of the directory serial No.
1 is the directory 1 before the erasure, that is, the directory 1 in which
nothing is recorded in the non-recorded region 1104 and that the content
of the file 1 which is managed by the directory 1 is corrected and is
again recorded onto the optical card by the same file name.

In FIG. 11, information indicating that the file 1 is rewritten by the same
file name as a correction data file 1 of the file 1 is sent from the host
in step S1 and is received by the MPU in step S2. A check is then made in
step S3 to see if the file is erased or not. If YES, namely, if the file
is erased, the erasure information is set to 1 in step S4. In step S5, a
check is made to see if the file is rewritten under the same file name or
not. If YES, step S6 follows and erasure information indicative of the
logical erasure, that is, a numeral 1 is recorded into the non-recorded
region 1104 of the directory 1. The file 1 becomes the file which has
first logically been erased on the optical card. The directory 1 of the
directory serial No. 1 so far is managed as an erasure directory 1. The
MPU confirms that the numeral 1 as erasure information has been recorded
in the non-recorded region 1104 of the directory 1. A check is again made
in step S3 to see if the file is erased or not. In this case, as shown in
FIG. 10, since the correction data file 1 and the directory 1 of the
directory serial No. 3 which manages the correction data file 1 are newly
recorded, the correction data file 1 is first recorded as a file 1 into
the file section. The directory 1 of the directory serial No. 3 is
subsequently recorded into the directory section 1023. At this time, no
information is recorded in the non-recorded region 1104 of the directory 1
and a region 1104 is in a space state.

Thus, the file 1 which has been managed by the file group in the normal
mode is managed by the file group in the erasure mode because the
directory 1 of the directory serial No. 1 to manage the file 1 is
registered as an erasure directory 1. The file 1 which is managed by the
directory 1 of the directory serial No. 3 which has newly been recorded is
managed by the file group in the normal mode. In FIG. 10, with respect to
the erasure of the files of the directory serial Nos. 2 to 4, 6 and 7
which are respectively managed as well, a file management is executed by
processes similar to the foregoing file management.

The case where the file is corrected and is again recorded by the same file
name has been described above. However, in the case of executing only the
erasure of the existing files, if it is determined in step S5 in FIG. 11
that the file is not rewritten (NO), a numeral 1 as erasure information is
recorded into the non-recorded region of the directory which manages the
file in step S7, thereby logically erasing the file. In this case as well,
the erased file is managed by the file group in the erasure mode. If NO in
step S3, the file and the directory are recorded in step S8.

A reproducing method of information recorded on the optical card will now
be described by using FIGS. 10 and 12. In step S10 in FIG. 12, the files,
directories, and erasure directories recorded on the optical card are
first reproduced by the reproducing operation of the information
recording/reproducing apparatus by a command from the host. The reproduced
information is sent to the MPU in step S11. The MPU checks a reference
numeral 1 as erasure information exists in the non-recorded region 1104 of
each directory or erasure directory or not in step S12. As a result of the
discrimination in step S12, a group of files which are managed by the
erasure directories of the directory serial Nos. 1 to 4, 6, and 7 in which
numeral 1 as erasure information exists are stored into the erasure mode
region in the host (step S13). A group of files which are managed by the
directories of the directory serial Nos. 5 and 8 to 10 in which no erasure
information exists are stored into the normal mode region in the host
(step S14). That is, a check is made in step S12 to see if the reproduced
information has been erased in the past or not, thereby distributing the
reproduced information by mode in accordance with the result of the
discrimination in step S12.

For each of the file groups stored in the host every mode, by selecting
each mode, the file names are displayed on the display in step S5. It is
now assumed that, in each mode, the file names are sequentially displayed
in accordance with the reading order from the optical card. In both modes,
by selecting the file name, a special file can be accessed and the
subsequent processes are executed in a manner similar to those in the file
management in the case of a floppy disc.

As mentioned above, in the third embodiment, the logically existing files
and the logically erased files can be managed as independent file groups.
Thus, while a file management is generally progressed for a group of
logically existing files, by selecting the erasure mode, a group of files
which have logically been erased in the past can be retrieved.

As shown in FIG. 13, it is also possible to construct the apparatus in a
manner such that the erasure information which is recorded into the
non-recorded region 1104 of the erasure directory is recorded as a serial
No. indicative of the number of erasing operation times of the files of
the same file name on the optical card and is managed. In the above
example as well, an effect similar to that in the third embodiment
mentioned above can be obtained. In the retrieval of the logically erased
files, the function can be further improved.

The recording method of the erasure directories is not limited to that in
the third embodiment but when the number of erasure directories has
reached a predetermined value, the erasure directories can be also
recorded into a special region on the optical card in a group from time to
time, when some predetermined number have been recorded. As a management
of the erasure directories, it is also possible to construct the apparatus
in a manner such that only a predetermined number of erasure directories
are used as objects to be managed, and in the case where the predetermined
number is set to, for instance, 5, when the erasing and updating
operations have been executed seven times, only five erasure directories
can be displayed from the erasure directory having a new erasure career.
By the above constructions as well, an effect similar to that in the third
embodiment is derived and the function of a file management can be
improved.